[amit@onyx]: man -k sleep Tcl_Sleep (3) - delay execution for a given number of milliseconds Tcl_Sleep [Sleep] (3) - delay execution for a given number of milliseconds apmsleep (1) - go into suspend or standby mode and wake-up later nanosleep (2) - pause execution for a specified time sleep (1) - delay for a specified amount of time sleep (3) - Sleep for the specified number of seconds usleep (1) - sleep some number of microseconds usleep (3) - suspend execution for microsecond intervals
The numbers in the second column show the Section umber for the manual page. So now we see several commands/calls that are related to sleeping. Find out more by doing man 3 sleep or man 1 sleep, where the number is the section number.
|Section||The human readable name|
|1||User commands that may be started by everyone.|
|2||System calls, that is, functions provided by the kernel.|
|3||Subroutines, that is, library functions.|
|4||Devices, that is, special files in the /dev directory.|
|5||File format descriptions, e.g. /etc/passwd.|
|7||Miscellaneous, e.g. macro packages, conventions.|
|8||System administration tools that only root user can execute.|
For example, if you want to find out more about the printf library call, you can simply look for it in Section 3 using the following command:
man 3 printf
Otherwise if you say man printf, you will get the first man page found, which happens to be in Section 1. This command describes a printf that you can use from the shell and is different from a printf used in a C program.
--help. For example, try